ES2273775T3 - LIGHTER FOR OXYGEN LAUNCH FOR THERMAL CUTTING, DRILLING, ETC. - Google Patents

Abstract

Method of ignition of an oxygen lance (13), in which highly concentrated oxygen of the lance (13) is supplied to a pyrophoric fine-grained metal powder that ignites in contact with oxygen and that during its combustion ignites a metal ignition charge (6a, 6b), and that together with the latter ensures the ignition of the lance (13), characterized in that the pyrophoric fine-grained metal powder, consisting of zirconium powder (7) or titanium , is arranged in a gas permeable container (8), preferably combustible, which in turn is disposed between the oxygen lance (13) and the ignition charge (6a, 6b), which consists of a mixture of metal powders , after which highly concentrated oxygen is supplied to the zirconium (7) or titanium powder through the gas permeable container (8), and thus ignites said zirconium (7) or titanium powder when the lance must blaze up.

Description

Lighter for cutting oxygen lance thermal, taladadro, etc.

The present invention relates to a new ignition method of an oxygen lance, in which oxygen Highly concentrated lance is supplied to a metal powder pyrophoric fine grain that ignites in contact with oxygen and that during its combustion ignites an ignition charge of metal, and that together with the latter ensures the ignition of the spear.

The method is mainly of the type that It works without supplementary electric arc.

The invention also relates to a lighter of oxygen lance operating according to the method of the invention, comprising a sleeve with an inside diameter that is greater than that of the mouth of the spear, said sleeve being intended, before that the lance ignites, to be displaced by sliding over the mouth of the spear until it reaches a mouth position specific, further comprising said spear lighter of oxygen a pyrophoric charge of starting the ignition.

A particular advantage of the method and the device (the lighter) according to the invention is that it can be used both in the air and underwater.

The oxygen lances of the type to which it is made reference in this case, which are mainly used for cutting and thermal drilling, and also underwater, in scrap yards and also in the steel industry, they comprise in principle two basic types, the first of which, which is the type to which reference in this case fundamentally, it works only with oxygen, and therefore requires some kind of function of separate on, while the second main type works with oxygen and its own supplementary electric arc.

A problem suffered so far by oxygen lances that don't have their own electric arc is that They have always been difficult to turn on. In the oxygen lances that they have their own electric arc, the arc is used to ignite Spear. There is also an intermediate variant, in which use a separate electric arc lighter to turn on the lance, which is then used completely separately with respect to the lighter, since it is no longer necessary after ignition.

The difficulty of lighting oxygen lances without access to an electric arc lies in the fact that the tip of the lance must be heated otherwise to the temperature of ignition of the steel, that is, around 1050 ° C. They have previously used several different methods when it comes to at the ignition of oxygen lances without access to electric arcs, and probably the two oldest methods are by a blowtorch of gas welding or by means of a coal fire. However, none of these methods has been especially popular, since the person who lights the spear must remain very close to the mouth of the spear and, if it gets too close to it, it could be reached by the jet of molten steel.

In document SE 7605274-5 describe a device or lighter something more perfected to light oxygen lances that do not have access to their own arc electric. The lighter described therein consists of a sleeve, open at one end, with a diameter with a cross section greater than that of the lance mouth. He sleeve is intended to be slid over the mouth of the spear, and retained therein by means of a spring adapted for such purpose. The sleeve itself is partially filled with a powder of metal and also with a primer that can be ignited by a ignition duct from the other closed end of the sleeve. From the description it is noted that it must be possible to turn on the primer, either by a cut-sensitive composition, arranged next to the outside of the closed end of the sleeve, or by chemicals contained in the ignition duct, that light themselves above the temperature ambient, so that the lighter can be turned on by a Small temperature rise The text also indicates that the lighter could contain pyrophoric substances, that is, those that come on when oxygen is supplied, and that in the if they were added to the ignition composition or to the primer could cause self-ignition when the supply of oxygen. However, the document does not describe proposals for suitable pyrophoric substances that could be used with this objective. In general terms, it could probably be said that to the point that the lighter described in this patent contains such "chemicals that ignite themselves above of the ambient temperature, so that ignition is possible by a small temperature rise, "the lighter in issue does not seem to be able to meet the requirements of security necessary, since in that case you must have a strong tendency towards accidental ignition.

In the Swedish printed patent application 8704421-0 another ignition device is described for similar oxygen lances, which states that the dust of combustion, that is, the dust load used for actual heating of the lance to the ignition temperature, may properly consist of aluminum powder, and that the surrounding sleeve should be provided with a stop that regulates to what extent the lance can be introduced into the sleeve, and also that the latter may also contain a stop mass that it consists, for example, of cotton, and also that it is possible set a pyrotechnic delay between a fuse head arranged at the end of the fundamentally closed sleeve and the primer arranged inside the sleeve, which, in this way, turn on the combustion powder. This arrangement allows that the person who turns on the outer primer can depart from the trajectory. In other aspects, the same are applicable comments for the device described above, since, given which must contain considerable amounts of pyrotechnic material, the special provisions that apply for such material also They must be applied to these lighters.

For additional references, see the document US-A-5 622 672, which discloses a ignition method of an oxygen lance, in which oxygen Highly concentrated lance is supplied to a metal powder pyrophoric contained in a metal container, air tight, said container being perforated so that the metal powder pyrophoric ignites in contact with oxygen and during its combustion ignites said container, thus ensuring the ignition of said spear, and also the document US-A-3 275 484, which discloses a pyrophoric charge consisting of zirconium or titanium.

The oxygen lances of the general type described in the patent descriptions mentioned above, with pyrotechnic loads as ignition medium, are available in the market for several years, and in practice it has been proven that have a high failure rate, and that have been required by part of the person using the spear an instinctive appreciation significant with respect to how quickly the oxygen supply to its maximum capacity.

Thus, the present invention relates to a new type of oxygen lance lighter that ignites only by applying oxygen and it does not contain any pyrotechnic primer, and therefore does not have to depend on No special safety regulation.

This is because, according to the method and the device according to the invention, the pure pyrotechnic primers previous to ignite the ignition loads (the dust of combustion) of the oxygen lance lighters are replaced by a small amount of pyrophoric metal powder, such as zirconium or titanium. Theoretically, phosphorus, which is clearly pyrophoric, it could also work, but the phosphorus it turns on with the air and therefore it is difficult to manipulate it in normal conditions, and thus is not indicated in this context. On the other hand, zirconium, which is the best alternative In our opinion, it is pyrophoric and is lit with high oxygen contents with the condition that there is a surface large enough, but not more flammable than wood normal with air, where the oxygen content is normally slightly higher than 20%. It is also appropriate that the spears of oxygen of the type referred to in this case are fed with completely pure oxygen or mixed oxygen with small amounts of inert gas, for example, approximately 5% argon, and that oxygen concentrations are more than suitable for lighting zirconium or titanium powder with a Active surface large enough.

Therefore, it can be stated in a general way that the oxygen lance lighter characteristic of the invention consists of an ignition charge of metal powder (powder of combustion) which is enclosed in a sleeve, closed by a end, with an inside diameter that is larger than the diameter outside of the oxygen lance, this sleeve being provided, when the spear must be ignited, to be slipped over the mouth of the spear until it reaches a certain specific depth, and a metal starting load being arranged in this sleeve pyrophoric powder, such as zirconium or titanium, in addition to the charge of ignition of metal powder, on top of this load ignition, that is, at the end directed towards the spear of oxygen. Neither large quantities of metal are necessary. pyrophoric for this purpose. If zirconium is selected, the best alternative according to our opinion, approximately 0.05 g to 0.5 g of pure fine grain zirconium with a size of 2 to 6 µm particles for this purpose. Start load Quickly turn on the used ignition charge consisting of 11 to 15 g of a mixture of iron / aluminum powder, in which the iron and aluminum components are present in a ratio of 1: 1 weight. It has also been able to establish that this burden of ignition is more effective if it comprises a first load part of finer grain and a second part of grain loading something else thick. Half the weight of a first part of the load produced of approximately 4.0 g therefore consists of aluminum powder with a particle size of approximately 0.1 mm, and the other half of its weight consists of iron powder with a size of particles of approximately 0.01 mm, while the second part It consists of 4.5 g of aluminum granules with a size of particles of 1 to 3 mm and in 4.5 g of iron filings with a particle size 0.4 to 0.8 mm.

With the oxygen lance lighter characteristic of the invention, it is already possible to carry out the ignition of any type of oxygen lance not equipped with an arc in the manner as easy as possible Since the oxygen lance lighter does not Contains no pure pyrotechnic material, neither is necessary No storage limitation. When the spear lighter oxygen ignites, the oxygen lance lighter simply placed in the place provided for it on the mouth of the lance, after which the supply of oxygen, causing the high oxygen content that the load of pyrophoric onset, consisting, for example, of powdered zirconium pure metallic, turn on and turn on the load of ignition consisting of iron / aluminum powder, which in turn Start the oxygen / iron combustion and ignite the lance. He Reliable ignition of any oxygen lance obtained from this mode is, of course, consequence to some extent of the high combustion temperature of zirconium, approximately 4900 ° C.

In addition to the basic idea of using a powder pyrophoric metal such as zirconium or titanium for the purpose of referenced in this case, the invention also includes a Detailed design of the oxygen lance lighter itself. In First, a pyrophoric metal powder is necessary, such as zirconium or titanium, and must be held in position at the same time that a sufficiently large surface of it must be available directly to come into contact with oxygen when your supply is activated. According to the invention, these requirements are achieved by placing pyrophoric metal powder in a gas permeable container, preferably combustible, directly on top of the ignition charge. In As for the material for this container, felt from ordinary machine, from which a cup or container with its own separate cover and internal volume which considerably exceeds the minimum volume that would be necessary for pyrophoric metal powder. Actually, it has proven that it is advantageous that most of the dust of pyrophoric metal easily forms a powder coating inside the felt container. In this way, you can use the large area of dust, which, in this way, is available to come into direct contact with oxygen. Directly under this felt container, it is arranged then the ignition charge itself, preferably as a mixture of iron / aluminum powder from a first part of finer grain and with a second mixture of coarser grain same materials, in this respect, these mixing parts can have the same size in terms of weight. It has also been checked that there is no special reason to separate the two parts of mixing with each other, but it is totally satisfactory if the they fill up one after the other in their common space in the lighter. On the contrary, it can even be an advantage if you have place a limited mixture in the boundary layer between the two parts of mixture.

The invention has been defined in all its characteristics in the successive patent claims, and it will be described below only in a somewhat more detailed way, referring to the representative design of it, shown in the attached figures, in which

Figure 1 shows an inclined projection in section of a lighter;

Figure 2 shows a sectional view of a lighter located on the tip of a spear in a spear of oxygen to be ignited;

Figure 3 shows the parts that make up a lighter on an inclined projection and on a smaller scale, Y

Figure 4 shows a sectional view of a lighter intended for use underwater, mounted on a spearhead intended for this.

The corresponding components have been indicated with the same reference numerals in the different figures, regardless of how and at what scale they are represented.

As can be seen in Figures 1 to 3, the outer part of the lance lighter according to the invention It consists of an outer tube (1) and an inner sleeve (2) that it is fixed on the outer tube (1) by means of a raised recess (4), which extends preferably forming a complete circle, housed in a notch (3) in the sleeve (2). Inner sleeve (2) is also provided with an inner hole (5) in which they are arranged two loading parts consisting of mixtures of powder of Iron / aluminum of different particle sizes. In the figure, the finest grain loading part has the reference (6a) and the thicker grain loading part has the reference (6b). Together, they constitute the ignition charge itself, but, in order to turn them on, the startup load is necessary characteristic of the invention, which therefore consists of approximately 0.15 g of zirconium (7) divided finely arranged in a cup or container (8) permeable to gas with a cover and, in the example shown, made of machine felt. He inner space (9) of the cup (8) is considerably larger than the volume of the zirconium powder itself (7), and the powder rests freely in space, in which it forms what could be described as a powder coating for the interior walls of the space (9). The inner sleeve (2) is also provided with a butt edge (10), whose function is, as shown in the Figure 2, ensure that the oxygen lance indicated as (13) can be guided to this top position, but not beyond. He inner sleeve (2) is also provided with two guide tabs (11) and (12) preferably somewhat elastic (see figure 3), whose function is, as can be seen in figure 2, guide the mouth of the lance (13) inside eccentrically along a inner edge of the tube (1), and also retain it in position during handling before switching on. Under positioning of the stop edge (10) between the outer end of the lance (13) and the cover of the cup (8), a space of interstitium (14) between the deck and the mouth of the spear, and this interstitium space is also provided with an outlet (15) located between the guide tabs (11) and (12), and this is the way in which oxygen can pass through it during the stage initial of the ignition process, and then back in the outside of the spear.

Therefore, in order to light the spear, it is it is necessary that the lighter be slid over the mouth of the spear to the stop position shown in figure 2, after which Activate the oxygen supply in the lance. What happens to continuation is that most of the oxygen passes through the interstitium (14) and exits through the exit (15) at the same time that part of the gas flows through the felt cover of the cup (8) and react with the zirconium powder, which ignites and then turn on the ignition charge (6) that ignites the reaction oxygen / iron, and the lance is ready for use.

The lighter variant according to the invention shown in figure 4 has an outer shell (1a) in which the tube (1) and the sleeve (2) of the variant shown in the figures 1 to 3 have been combined in one unit. In this unit (1st), the guide tabs (11) and (12) have been replaced by firm guide protuberances, designated in this case as (11a). The lighter is also adapted for use under the water and therefore is provided with a sealing collar elastic (16), and could also be provided with a sheet protective (17) on the top of the capsule (8) with its load Pyrophoric onset. In such a case, the resistance of the protective sheet (17) must be adapted so that it jumps in pieces when the oxygen supply is activated. Of course, both the protective foil and the sealing collar could be used out of water

Another possible variant that has not been illustrated in one figure is to mount a spear part with a lighter to Form a single unit. This variant might be appropriate when what is required is fundamentally a large number of spears very short for use with relatively short interruptions or Long between several uses. An area of activity of this type It could be shipwreck work.

Claims (12)

1. Method of ignition of an oxygen lance (13), in which highly concentrated oxygen from the lance (13) is supplied to a pyrophoric fine-grained metal powder that ignites in contact with oxygen and which during combustion ignites a metal ignition charge (6a, 6b), and that together with the latter ensures the ignition of the lance (13), characterized in that the fine-grained pyrophoric metal powder, consisting of zirconium powder (7) or titanium, is arranged in a gas permeable container (8), preferably combustible, which in turn is disposed between the oxygen lance (13) and the ignition charge (6a, 6b), consisting of a mixture of powders of metals, after which highly concentrated oxygen is supplied to the zirconium (7) or titanium powder through the gas permeable container (8), and thus ignites said zirconium (7) or titanium powder when the Lance must ignite. 2. Oxygen lance lighter, operating according to the method of claim 1, comprising a sleeve (1) with an inside diameter that is larger than that of the lance mouth (13), said sleeve being provided, before that the lance is ignited, to be slid over the lance's mouth until it reaches a specific mouth position (10), said oxygen lance lighter further comprising a pyrophoric ignition charge (7), and an ignition charge (6a, 6b) consisting of metal powder, characterized in that the ignition charge (6a, 6b) is enclosed in the sleeve (1), which has an internal diameter that is larger than that of the lance's mouth (13 ), also containing said sleeve (1), in addition to said ignition charge (6a, 6b) consisting of metal powder, the pyrophoric start charge (7), consisting of zirconium (7) or pure metallic titanium arranged in a gas permeable container (8), preferably combustible. 3. The oxygen lance lighter according to claim 2, characterized in that said gas permeable container (8), preferably combustible, is disposed between the mouth position (10) of the oxygen lance (13) in the sleeve and the ignition charge (6a, 6b). 4. Oxygen lance lighter according to claim 3, characterized in that said starting charge (7) consists of 0.05 to 0.5 g of pure metal powder zirconium with a particle size of about 2 to 6 µm . 5. An oxygen lance lighter according to claim 3 or 4, characterized in that said gas permeable container (8), in which the pyrophoric metal powder (7) is stored in the outlet, is made of porous felt. 6. An oxygen lance lighter according to claim 5, characterized in that the container (8) made of gas permeable material is designed as a cup made of porous felt provided with a cover that covers it completely made of the same felt material, considerably exceeding the inner volume (9) of the cup the total volume of pyrophoric metal powder (7). 7. Oxygen lance lighter according to any one of claims 1 to 6, characterized in that the ignition charge (6a, 6b) consists of a mixture of iron and aluminum powder. 8. The oxygen lance lighter according to claim 7, characterized in that the ignition charge (6a, 6b) comprises a first part of the finest grain load (6a) and a second part of the somewhat thicker grain load (6b ), containing both iron and aluminum loading parts in a 1: 1 weight ratio. 9. An oxygen lance lighter according to claim 8, characterized in that the ignition charge (6a, 6b) included therein comprises a first charge part (6a) containing iron powder with particles with a size of the order of 0.01 mm and aluminum particles with a size of the order of 0.1 mm, and also a second load part (6b) of coarser grain containing iron dust with particles with a size of the order of 0.4 to 0.8 mm and aluminum granules with a size of the order of 1 to 3 mm. 10. Oxygen lance lighter according to claim 9, characterized in that the finest grain loading part (6a) of the ignition charge (6a, 6b) is arranged directly adjacent to the gas permeable container in which it is arranged pyrophoric metal powder (7). 11. Oxygen lance lighter according to any one of claims 1 to 9, characterized in that it consists of an outer tube part (1) open at both ends, with an inner diameter greater than that of the oxygen lance, an inner sleeve (2) which is fixed in said part of the outer tube by means of an embossed recess (4) housed in a notch (3) provided for that purpose and which is completely closed at one end, and in which the ignition and start loads (6a, 6b) are inserted inside an inner duct or hole (5) disposed therein, said inner sleeve (2) also having at least two guide tongues (11, 12) provided to guide the mouth of the oxygen lance (13) inside and hold it firmly directly on the inner duct (5) of the sleeve, and also a stop flange (10) that limits the introduction of the lance inside the sleeve to a position before that reaches the load of ini cio, and also a gas flow outlet opening (15) that allows the gas to flow out of the lance to flow out of space directly over the starting load and backward when the lance passes. 12. Oxygen lance lighter (1a) according to any of the preceding claims, intended primarily for use underwater, characterized in that it comprises an elastic sealing collar (16) surrounding its end directed towards the lance (13) and the close mouth of the lance, and also a protective sheet (17) that initially covers the pyrophoric metal powder (7), and whose resistance is selected so that it jumps to pieces when oxygen is supplied.